NAME
filter - cups file conversion filter interface
SYNOPSIS
filter job user title num-copies options [ filename ]
DESCRIPTION
The CUPS filter interface provides a standard method for adding support for new document types to CUPS. Each filter is capable of converting from one or more input formats to another format that can either be printed directly or piped into another filter to get it to a printable format.
Filters must be capable of reading from a filename on the command-line or from the standard input, copying the standard input to a temporary file as required by the file format. All output must be sent to the standard output.
The command name (argv[0]) is set to the name of the destination printer.
LOG MESSAGES
Messages sent to stderr are generally logged to printer-state-message attribute and the current ErrorLog. Each line begins with a standard prefix:
| ALERT: message | |
| Sets the printer-state-message attribute and adds the specified
message to the current ErrorLog using the "alert" log level.
| |
| ATTR: attribute=value [attribute=value] | |
| Sets the named job attribute(s). Typically this will be used to
set the job-remote-id attribute.
| |
| CRIT: message | |
| Sets the printer-state-message attribute and adds the specified
message to the current ErrorLog using the "critical" log level.
| |
| DEBUG: message | |
| Sets the printer-state-message attribute and adds the specified
message to the current ErrorLog using the "debug" log level.
| |
| DEBUG2: message | |
| Sets the printer-state-message attribute and adds the specified
message to the current ErrorLog using the "debug2" log level.
| |
| EMERG: message | |
| Sets the printer-state-message attribute and adds the specified
message to the current ErrorLog using the "emergency" log level.
| |
| ERROR: message | |
| Sets the printer-state-message attribute and adds the specified
message to the current ErrorLog using the "error" log level.
| |
| INFO: message | |
| Sets the printer-state-message attribute. If the current LogLevel
is set to "debug2", also adds the specified message to the
current ErrorLog using the "info" log level.
| |
| NOTICE: message | |
| Sets the printer-state-message attribute and adds the specified
message to the current ErrorLog using the "notice" log level.
| |
|
PAGE: page-number #-copies
PAGE: total #-pages | |
| Adds an entry to the current PageLog. The first form adds
#-copies to the job-media-sheets-completed attribute. The second
form sets the job-media-sheets-completed attribute to #-pages.
| |
|
STATE: printer-state-reason [printer-state-reason ...]
STATE: + printer-state-reason [printer-state-reason ...] STATE: - printer-state-reason [printer-state-reason ...] | |
| Sets, adds, or removes printer-state-reason keywords to the
current queue. Typically this is used to indicate media, ink, and
toner conditions on a printer.
| |
| WARNING: message | |
| Sets the printer-state-message attribute and adds the specified
message to the current ErrorLog using the "warning" log level.
| |
ENVIRONMENT VARIABLES
The following environment variables are defined by the CUPS server when executing the filter:
| CHARSET | |
| The default text character set, typically utf-8.
| |
| CLASS | When a job is submitted to a printer class, contains the name of
the destination printer class. Otherwise this environment
variable will not be set.
|
| CONTENT_TYPE | |
| The MIME type associated with the file (e.g.
application/postscript).
| |
| CUPS_DATADIR | |
| The directory where data files can be found.
| |
| CUPS_SERVERROOT | |
| The root directory of the server.
| |
| DEVICE_URI | |
| The device-uri associated with the printer.
| |
| FINAL_CONTENT_TYPE | |
| The MIME type associated with the printer (e.g.
application/vnd.cups-postscript).
| |
| LANG | The default language locale (typically C or en).
|
| PATH | The standard execution path for external programs that may be run by
the filter.
|
| PPD | The full pathname of the PostScript Printer Description (PPD)
file for this printer.
|
| PRINTER | |
| The name of the printer.
| |
| RIP_CACHE | |
| The recommended amount of memory to use for Raster Image
Processors (RIPs).
| |
| SOFTWARE | |
| The name and version number of the server (typically CUPS/1.2).
| |
| TZ | The timezone of the server.
|
| USER | The user executing the filter, typically "lp" or "root"; consult the
cupsd.conf(5) file for the current setting.
|
COMPATIBILITY
While the filter interface is compatible with System V interface scripts, it will only work with the System V interface script as the only filter. Typically the interface script will be provided via the lpadmin(8) command using the -i option.
SEE ALSO
backend(1), cupsd(8), http://localhost:631/help
COPYRIGHT
Copyright 2007 by Apple Inc.
